Russian 6.53 rifle?

I'm reading a book called Negroes with Guns (http://www.amazon.com/Negroes-Guns-African-American-Life/dp/0814327141/ref=pd_bbs_1/104-3279795-5325534?ie=UTF8&s=books&qid=1185371035&sr=8-1) by Robert F. Williams (http://en.wikipedia.org/wiki/Robert_F._Williams) about armed self-defense in the South during the civil rights movement. In it, he mentions the use of a Soviet made rifle called the 6.53. He describes it as a civilian bolt-action. I've never heard of it and I can't seem to find anything about it online.